Wavelet analysis of the magnetotail response to solar wind fluctuations during HILDCAA events
<p>In this work a study of the effects of the high-intensity long-duration continuous AE activity (HILDCAAs) events in the magnetotail was conducted. The aim of this study was to search the main frequencies during HILDCAAs in the <span class="inline-formula"><i>B</i>...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2019-10-01
|
| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/37/919/2019/angeo-37-919-2019.pdf |
| Summary: | <p>In this work a study of the effects of the high-intensity
long-duration continuous AE activity (HILDCAAs) events in the magnetotail
was conducted. The aim of this study was to search the main frequencies
during HILDCAAs in the <span class="inline-formula"><i>B</i><sub><i>x</i></sub></span> component of the geomagnetic field in the
magnetotail, as well as the main frequencies, at which the magnetotail
responds to the solar wind during these events. In order to conduct this
analysis the wavelet transform was employed during nine HILDCAA events that
coincided with Cluster spacecraft mission crossing through the tail of the
magnetosphere from 2003 to 2007. The most energetic periods for each event
were identified. It was found that 76 % of them have periods <span class="inline-formula">≤4</span> h. With the aim to search the periods that have the highest
correlation between the IMF <span class="inline-formula"><i>B</i><sub><i>z</i></sub></span> (OMNI) component and the Cluster <span class="inline-formula"><i>B</i><sub><i>x</i></sub></span>
geomagnetic field component, the cross wavelet analysis technique was also
used in this study. The majority of correlation periods between the <span class="inline-formula"><i>B</i><sub><i>z</i></sub></span> (IMF)
and <span class="inline-formula"><i>B</i><sub><i>x</i></sub></span> component of the geomagnetic field observed also were <span class="inline-formula">≤4</span> h,
with 62.9 % of the periods. Thus the magnetotail responds stronger to IMF
fluctuations during HILDCCAS at 2–4 h scales, which are typical substorm
periods. The results obtained in this work show that these scales are the
ones on which the coupling of energy is stronger, as well as the modulation
of the magnetotail by the solar wind during HILDCAA events.</p> |
|---|---|
| ISSN: | 0992-7689 1432-0576 |